Obese subjects will receive a complex nutrient drink (Ensure Plus; 17 % protein, 30 % fat and 53 % carbohydrate, 1 kcal/mL). Nutrient intake will be stopped when subjects had reached maximal or unbearable satiation; the time needed to reach the maximal level of satiation (tmax) and the quantity of volume drunk will be recorded and calorie intake calculated.

Dietary Supplement: ensure plus

17 % protein, 30 % fat and 53 % carbohydrate; 1 kcal/mL

Active Comparator: gastric emptying_obese weight

Obese subjects will receive a standardized meal, consisting of two scrambled eggs (cooked with 10 g butter), placed on two slices of whole wheat bread and 200 mL of milk (in total: 468 kcal). The test meal will be labeled with 100 mg of 13C-octanoic acid for determination of gastric emptying.

Normal weight subjects will receive a standardized meal, consisting of two scrambled eggs (cooked with 10 g butter), placed on two slices of whole wheat bread and 200 mL of milk (in total: 468 kcal). The test meal will be labeled with 100 mg of 13C-octanoic acid for determination of gastric emptying.

Normal weight subjects will receive a complex nutrient drink (Ensure Plus; 17 % protein, 30 % fat and 53 % carbohydrate, 1 kcal/mL). Nutrient intake will be stopped when subjects had reached maximal or unbearable satiation; the time needed to reach the maximal level of satiation (tmax) and the quantity of volume drunk will be recorded and calorie intake calculated.

Obesity has reached pandemic proportions, obesity-associated complications are extensive and the current treatment options are limited. These facts demonstrate the need for an improved understanding of the pathogenesis of obesity. The gastrointestinal tract plays a key element in the control of satiation; discrepancies exist, however, for the role of gastric and intestinal parameters in the control of satiation in relation to body mass. To achieve a comprehensive understanding for the reciprocal control between gastric functions and intestinal parameters in the development of satiation in obese people the investigators will compare satiation parameters, gastric emptying and plasma glucagon-like peptide-1 (GLP-1), peptide tyrosine tyrosine (PYY) and ghrelin levels between normal and obese healthy volunteers.

Time needed to reach the level of satiation and total calorie intake will be measured by a standardized nutrient drink test; gastric emptying of solids by a 13C-octanoic acid breath test; and plasma GLP-1, PYY and ghrelin levels will be measured after a standardized nutrient drink.

Eligibility

Ages Eligible for Study:

18 Years to 45 Years (Adult)

Sexes Eligible for Study:

All

Accepts Healthy Volunteers:

Yes

Criteria

Inclusion Criteria:

healthy subjects

age 18-45

Exclusion Criteria:

smoking

substance abuse

regular intake of medication

medical or psychiatric illness

gastrointestinal disorders or food allergies

Contacts and Locations

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To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below.
For general information, see Learn About Clinical Studies.

Please refer to this study by its ClinicalTrials.gov identifier: NCT01456572